Please help my dd with this so-called "very easy" pattern!

[swampwitch0]

Hi 👋
My dd has agreed to make a dress for a friend for a ball.
She's just done gcse textiles and is hopefully going to do a F&T btec 🤞
The pattern is Vogue very easy make 9343. It says "very easy" 🤔 and the skirt has been fine, but we can't understand how to put the top halter piece together (other reviewers say its really not suitable for beginners but.l to late now...)
Has anyone made this dress? Any tips? She's very stressed 😫
Fabric is black crepe back satin.
Help!

You sew it onto the outside and then it folds into the inside, then you top stitch from the outside to stop it folding out again.

Ah!
Thats what I thought!
Thank you